In the Egyptian portion of the Libyan Desert, there’s a cave called “The Cave of Beasts” that contains over 5,000 cave paintings.

Also known as Wadi Sura II, the cave was only discovered in 2002 by amateur explorers. Among the depictions of animals and dancing humans, there’s a curious portion of wall covered in hundreds of hand prints. The cave art was created at least 7,000 years ago, using the technique of placing a hand on the wall and then blowing paint on top, like a stone-age spray can and stencil.

Within the mishmash of hands, there are 13 smaller hand prints, often placed in the palm of a larger print. Until now, archaeologists assumed the tiny prints belong to a baby, to express some kind of intimacy. However, some new research by archaeologists from the McDonald Institute for Archaeological Research at Cambridge University has suggested these are actually the hand prints of reptiles.

The researchers of the study, published in the Journal of Archaeological Science, came to this idea by looking at the size of the hand prints and comparing them to the size and dimensions of newborn baby hands.

(a) a newborn from Sample B, (b) a 4-year old Crocodylus from the zoological garden of the University of Tel Aviv, (c) an adult Varanus griseus from the wild, (d) an adult Varanus griseus from the Zoo of Moscow. Emmanuelle Honoré/McDonald Institute for Archaeological Research.

They gathered data on the size and dimension of human baby hands with the help of 36 new born babies and 25 premature babies, alongside 30 adult human hands. After comparing this information with the data obtained from the tiny hand prints, the study says the prints "differ significantly in size, proportions and morphology from human hands," meaning there’s an “extremely low probability” these are human.

Monitor lizard (Varanus griseus), found across North Africa and South Asia. edmon/Shutterstock

The team found that the proportions and the distance between each of the fingers were consistent with that of a reptile. With their knowledge of which animals lived in the Libyan desert at the time and other examples of cave art animal drawings, the archaeologists currently believe it was most likely to be a desert monitor lizard (Varanus griseus). At the moment, they’re also analyzing the forefeet of Nile crocodiles (Crocodylus niloticus) as a potential suspect. This could open up even more questions, as the crocodile would have to have been transported across the desert to the cave.

But why ancient dwellers of the Libyan desert would use a reptile foot as a stencil is unclear. This corner of the world has very little record of animal stencils, compared to Australian and South American rock art, which has a fair few examples, including some stenciles of emu feet. It is known that the monitor lizard had a symbolic, and possibly spiritual, connection to the ancient Saharan people. However, the researchers are cautious of jumping to conclusions.

Emmanuelle Honoré, the study leader, explained to National Geographic: "We have a modern conception that nature is something that humans are separate from.

"But in this huge collection of images we can detect that humans are just part of a bigger natural world. It's very challenging for us as researchers to interpret these paintings since we have a culture that's totally different. "